Food refrigeration appliance with illuminated shelves, and method of producing the illuminated shelves

ABSTRACT

There is described a food refrigeration appliance ( 1 ) having a casing ( 2 ); a food refrigeration chamber ( 3 ) housed inside the casing ( 2 ); a food-supporting shelf ( 5 ) located inside the refrigeration chamber ( 3 ); and a lighting system ( 7 ), in turn having a number of spot light sources ( 7   a ) fixed stably to the shelf ( 5 ), and a power line ( 8 ) for electrically powering the spot light sources ( 7   a ); the lighting system ( 7 ) having a number of straight tracks ( 14 ) made of electrically conducting material and fixed stably to the shelf ( 5 ) to define an electric circuit ( 9 ) connecting the spot light sources ( 7   a ) to the power line ( 8 ).

TECHNICAL FIELD

The present invention relates to a food refrigeration appliance withilluminated shelves, and to a method of producing the illuminatedshelves.

More specifically, the present invention relates to corresponding to anelectric household appliance, such as a freezer or refrigerator, towhich the following description refers purely by way of example.

BACKGROUND ART

As is known, home refrigerators have one or more refrigeration chambersinside for cooling or freezing food, and which are divided intocompartments by a number of horizontal shelves spaced apart inside therefrigeration chamber to support the food; and a lighting system forlighting the space inside the compartments defined by the shelves, sothat the food is clearly visible from outside the refrigeration chamber.

More specifically, some last-generation lighting systems comprise anumber of lighting devices fixed stably to the shelves to light thespace below and/or above the shelves; a main electric power linenormally located outside the refrigeration chamber; and a number ofelectric circuits wired directly on the shelves to connect the lightingdevices to the main electric power line. Shelves with lighting devicesas described above are normally referred to as “illuminated” shelves.

Each lighting device normally comprises an overhead light, in turncomprising a supporting member fixed stably to the shelf, and a bulbfitted to the supporting member; and each electric circuit comprises anumber of electric wires or cables connecting the bulb to the mainelectric line by means of an intermediate connector on the shelf.

The above lighting systems have numerous drawbacks.

First and foremost, “illuminated” shelves as described above areextremely complicated and awkward to produce, by involving fixing eachoverhead light to the respective shelf; connecting the electric cableselectrically to both the bulb and the intermediate electric connector;and gluing the electric cables along predetermined paths on theunderside of the shelf, e.g. along the outer peripheral edge of theshelf. As a result, the above manufacturing method obviously greatlyincreases the overall assembly time, and therefore the final productioncost, of the refrigerator.

Moreover, attaching electric cables to illuminated shelves oftransparent material, such as glass or Plexiglas, produces numerousshadow regions inside the refrigeration chamber compartments, which,besides reducing visibility of the foodstuffs on the shelves, creates anunsightly overall effect inside the refrigeration chamber. Being fairlythick, the electric cables, in fact, create unsightly straight greylines on the surfaces of the shelves, which are clearly visible from theoutside when the refrigeration chamber is opened.

Moreover, the electric cables form bacteria-accumulating areas on theshelves, which are difficult to clean, and, during routine cleaning, aresubject to damage or accidental detachment from the surface of theshelf.

DISCLOSURE OF INVENTION

It is an object of the present invention to provide a food refrigerationappliance with illuminated shelves, which eliminates accumulation ofbacteria on the shelves caused by the electric circuit, simplifiescleaning of the shelves, and eliminates the formation of shadow regionsinside the refrigeration chamber.

It is a further object of the present invention to provide a highlystraightforward, low-cost method of producing illuminated shelves.

According to the present invention, there is provided a foodrefrigeration appliance as claimed in Claim 1 and, preferably, in anyone of the following Claims depending directly or indirectly on Claim 1.

According to the present invention, there is also provided a method ofproducing illuminated shelves for food refrigeration appliances, asclaimed in Claim 12 and, preferably, in any one of the following Claimsdepending directly or indirectly on Claim 12.

BRIEF DESCRIPTION OF THE DRAWINGS

A non-limiting embodiment of the present invention will be described byway of example with reference to the accompanying drawings, in which:

FIG. 1 shows a view in perspective of a food refrigeration appliance inaccordance with the teachings of the present invention;

FIG. 2 shows a schematic view in perspective, with parts enlarged forclarity, of an illuminated shelf of the FIG. 1 appliance;

FIG. 3 shows a schematic side view, with parts removed for clarity, ofan illuminated shelf of the FIG. 1 appliance;

FIG. 4 shows a schematic view in perspective of a variation of theilluminated shelf of the FIG. 1 appliance;

FIG. 5 shows a schematic side view, with parts removed for clarity, ofthe illuminated shelf in FIG. 4;

FIG. 6 shows a track fixing step forming part of the method forproducing the illuminated shelf in FIGS. 2 and 3;

FIG. 7 shows a LED fixing step forming part of the method for producingthe illuminated shelf in FIGS. 2 and 3;

FIG. 8 shows a protective layer application step forming part of themethod for producing the illuminated shelf in FIGS. 2 and 3;

FIG. 9 shows a track fixing step forming part of the method forproducing the illuminated shelf in FIGS. 4 and 5;

FIG. 10 shows a LED fixing step forming part of the method for producingthe illuminated shelf in FIGS. 4 and 5;

FIG. 11 shows a protective layer application step forming part of themethod for producing the illuminated shelf in FIGS. 4 and 5; and

FIG. 12 shows a schematic view in perspective, with parts enlarged forclarity, of an illuminated shelf in accordance with an alternativeembodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Number 1 in FIG. 1 indicates as a whole a food refrigeration applianceparticularly advantageous for home use.

In the FIG. 1 embodiment, refrigeration appliance is a refrigerator,which substantially comprises a preferably, though not necessarily,parallelepiped-shaped casing 2 extending along a preferably, though notnecessarily, vertical axis A, and resting on the floor; and at least onerefrigeration chamber 3 inside casing 2 and for housing food forrefrigeration.

Refrigeration appliance 1 also comprises a door 4 for closingrefrigeration chamber 3, and which is hinged to a preferably, though notnecessarily, lateral side of casing 2, alongside the access opening torefrigeration chamber 3, to rotate, about an axis parallel to axis A, toand from a closed position closing refrigeration chamber 3.

In the FIG. 1 example, refrigeration chamber 3 is substantiallyparallelepiped-shaped, and houses a number of shelves 5, eachsubstantially horizontal to support the food for refrigeration.

More specifically, each shelf 5 is preferably, though not necessarily,rectangular, and rests on a known supporting member (not shown) insiderefrigeration chamber 3.

More in detail, each shelf 5 has a first food-supporting surface and asecond opposite surface and is adapted to be located inside therefrigeration chamber 3

In the FIG. 1 example, each shelf 5 is made of transparent orsemitransparent, electrically insulating material, such as glass, orplastic material such as Plexiglas, and rests firmly, but in easilyremovable manner, on the known supporting member (not shown) insiderefrigeration chamber 3.

Refrigeration appliance 1 also comprises a lighting system 7, in turncomprising a number of spot light sources 7 a fixed stably to at leastone of the two major surfaces of each shelf 5; and an external powerline 8 (shown by a dash line) for electrically powering light sources 7a.

Lighting system 7 also comprises, for each shelf 5, an electric circuit9 for powering light sources 7 a on shelf 5; and an electric connectingsystem 10 connecting external power line 8 electrically to electriccircuit 9 to power light sources 7 a.

Electric connecting system 10 is known and not described in detail,except to state that it may comprise a number of electric connectors 10a located on each shelf 5 and on the inner wall of refrigeration chamber3, and designed to connect electrically to one another, when shelf 5 islocated inside refrigeration chamber 3, to connect electric circuit 9 toexternal power line 8.

Alternatively, electric connecting system 10 may be an induction systemcomprising a first and second coil (not shown) located inside shelf 5and on the wall of refrigeration chamber 3 respectively, and wherein thesecond coil is connected to external power line 8 and generates amagnetic field which induces a predetermined current supply in the firstcoil connected to electric circuit 9 to power light sources 7 a.

With reference to FIGS. 1 and 2, unlike known lighting systems, electriccircuit 9 of lighting system 7, as opposed to comprising electric wiresor cables, comprises, for each shelf 5, a number of tracks 14 made ofelectrically conducting material and appropriately arranged on an outersurface 5 a of shelf 5 to connect electrically to light sources 7 a onshelf 5.

More specifically, in the FIG. 2 example, tracks defining electriccircuit 9 have preferably, though not necessarily a matrix-typegeometric configuration, and define on shelf 5 a number of power pointsPi, each connectable to a light source 7 a.

Tracks 14 extend in preferably, though not necessarily, curve (FIG. 12)or straight directions (FIG. 2) on the outer surface 5 a of shelf 5, andmay be made of at least partly conducting materials, such aselectrically conducting paint, and/or electrically conducting,silver-based ink, and/or copper-based ink, and/or aluminium-based ink,and/or any other similar type of electrically conducting material thatcan be fixed stably to a surface.

Light sources 7 a are conveniently spot light sources and may compriseLEDs and/or OLEDs (Organic Light Emitting Diode) and/or miniaturizedincandescent light bulbs and/or miniaturized fluorescent lamps and/orany other similar type of micro-lamp.

In the FIGS. 2 and 3 example, each light sources 7 a comprise aminiaturized, preferably SMD (Surface Mounting Device) LED 15characterized by an extremely small thickness, i.e. of about amillimeter. It should be pointed out that, besides being smaller,miniaturized SMD LEDs 15 differ from conventional PTH (PIN ThroughHoles) LEDs, by being connectable electrically to the supporting surfaceof an electric circuit with no connecting holes required on thesupporting surface.

In the FIGS. 2 and 3 example, miniaturized LEDs 15 are fixed to surface5 a of shelf 5 at connecting points Pi. More specifically, miniaturizedLEDs 15 may be glued to the tracks 14 with electric conductive glueand/or joint with the tracks 14 by welding.

In the FIGS. 4 and 5 embodiment, tracks 14 of electric circuit 9 arefixed to outer surface 5 a of shelf with the interposition of asupporting sheet 16 of insulating material.

More specifically, straight tracks 14 of electric circuit 9 are fixedstably to a supporting sheet 16 made of plastic material and having anadhesive surface 16 a fixed to surface 5 a of shelf 5.

More specifically, in the FIG. 5 example, supporting sheet 16 comprisesa polyethylene film having an adhesive inner surface 16 a fixed stablyto surface 5 a of shelf 5, and a visible surface 16 b to which tracks 14of electric circuit 9 are fixed stably.

It should be pointed out that, as opposed to visible surface 16 b,tracks 14 of electric circuit 9 may be fixed to adhesive surface 16 a ofsupporting sheet 16 fixed to surface 5 a of shelf 5.

Miniaturized LEDs 15 are fixed to the surface of supporting sheet 16 towhich straight tracks 14 are fixed. More specifically, in the FIG. 5example, miniaturized LEDs 15 are fixed to visible surface 16 b ofsupporting sheet 16, at connecting points Pi of tracks 14.

If tracks 14 are fixed to adhesive surface 16 a of supporting sheet 16,however, the miniaturized LEDs may be fixed to adhesive surface 16 a.

With reference to FIGS. 2 and 3, lighting system 7 may also comprise aprotective layer 18 fixed to surface 5 a of shelf 5 to cover tracks 14and/or miniaturized LEDs 15.

Protective layer 18 may, for example, comprise a protective paint or asheet of insulating material, e.g. plastic, with an adhesive surface.

The following is a description of the method of producing illuminatedshelves 5 of refrigeration appliance 1 as described above.

With reference to FIGS. 6 and 9, a first step comprises fixing tracks 14of electrically conducting material stably to outer surface 5 a of shelf5, so as to form on the shelf electric connecting circuit 9 for poweringlight sources 7 a.

More specifically, with reference to FIG. 6, straight tracks 14 ofelectrically conducting material may be fixed to outer surface 5 a ofshelf 5 by depositing and/or stamping a number of lines in electricallyconducting ink or paint. More specifically, straight tracks 14 ofelectrically conducting material may be screen printed on outer surface5 a of shelf 5.

Alternatively (FIG. 9), tracks 14 may be fixed to surface 5 a of shelf 5by applying supporting sheet 16, to which tracks 14 are applied, to thesurface of shelf 5.

It should be pointed out that tracks 14 may be fixed to surface 5 a todefine an electric connecting circuit substantially in the form of agrid or matrix.

Once tracks 14 are fixed to surface 5 a, the method comprises fixingminiaturized LEDs 15 to surface 5 a of shelf 5 (FIG. 7) or to visiblesurface 16 b of supporting sheet 16 (FIG. 10) to connect them to tracks14 at points Pi.

The method may also comprise applying a protective layer 18 ofinsulating material to surface 5 a of shelf 5 to cover tracks 14.

More specifically, this step may comprise applying a protective layer ofelectrically insulating paint to surface 5 a of shelf 5 to coverstraight tracks 14 and/or miniaturized LEDs 15 (FIG. 8), or applying afilm of protective insulating material on top of straight tracks 14and/or miniaturized LEDs 15 (FIG. 11).

Refrigeration appliance 1 has numerous advantages.

First and foremost, the small thickness of the electrically conductingtracks and miniaturized lighting source, such as the miniaturized LEDsprevents bacteria accumulating in the shelf, thus making the shelfeasier to clean, and, combined with the protective layer, safeguardsagainst accidental damage to the tracks or miniaturized LEDs on theshelf.

Moreover, assembling the lighting system is extremely cheap and easy, bycomprising only two straightforward operations: applying the tracks tothe shelf, and applying the miniaturized LEDs to predetermined powerpoints Pi. In the event track supporting sheet 16 is applied, the secondoperation may obviously be performed advantageously before applyingsupporting sheet 16 to shelf 5.

Clearly, changes may be made to the refrigeration appliance and to themethod of producing an illuminated shelf as described and illustratedherein, without, however, departing from the scope of the presentinvention as defined in the accompanying Claims.

The invention claimed is:
 1. A food refrigeration appliance (1)comprising a casing (2); a food refrigeration chamber (3) housed insidesaid casing (2); at least one shelf (5) having a first food-supportingsurface and a second opposite surface and adapted to be located insidesaid refrigeration chamber (3); and a lighting system (7), in turncomprising a number of light sources (7 a) fixed to said shelf (5), andpower means (8, 10) for electrically powering said light sources (7 a);said appliance being characterized in that said lighting system (7)comprises a protective layer (18) of electrically insulating materialapplied to at least one of said surfaces of the shelf (5) and a numberof electrically conductive tracks (14) associated to at least one ofsaid surfaces of the shelf (5) to define an electric circuit (9)connecting said light sources (7 a) to said power means (8, 10).
 2. Afood refrigeration appliance (1) comprising a casing (2); a foodrefrigeration chamber (3) housed inside said casing (2); at least oneshelf (5) having a first food-supporting surface and a second oppositesurface and adapted to be located inside said refrigeration chamber (3);power means (8, 10) for electrically powering a number of light sources(7 a) fixed to said shelf (5), and a lighting system (7), in turncomprising said light sources (7 a) fixed to said shelf (5), a number ofelectrically conductive tracks (14) associated to at least one of saidsurfaces of the shelf (5) to define an electric circuit (9) connectingsaid light sources (7 a) to said power means (8, 10), and a supportingsheet (16) of electrically insulating material, wherein the lightsources (7 a) and the electrically conductive tracks (14) are providedon said supporting sheet (16) and the supporting sheet is applied to atleast one of said surfaces of the shelf (5).
 3. An appliance as claimedin claim 2, wherein said electrically conductive tracks (14) are made ofelectrically conducting material deposited on said supporting sheet(16).
 4. An appliance as claimed in claim 2, wherein said supportingsheet (16) has an adhesive surface (16 a) adapted to be glued to atleast one of said surfaces of the shelf (5).
 5. An appliance as claimedin claim 2, wherein said supporting sheet (16) is made of transparent orsemitransparent plastic material.
 6. An appliance as claimed in claim 1,wherein said electrically conductive tracks (14) are made ofelectrically conducting material deposited on at least one of saidsurfaces of the shelf (5).
 7. An appliance as claimed in claim 2,wherein said lighting system (7) comprises a protective layer (18) ofelectrically insulating material applied to at least one of saidsurfaces of the shelf (5) or to said supporting sheet (16) so as tocover the electrically conductive tracks (14).
 8. An appliance asclaimed in claim 7, wherein said protective layer (18) is made oftransparent or semitransparent material.
 9. An appliance as claimed inclaim 1, wherein said shelf (5) is made of transparent orsemitransparent plastic material.
 10. An appliance as claimed in claim1, wherein said light sources (7 a) comprise light emitting diodes (15).11. An appliance as claimed in claim 1, wherein said electricallyconductive tracks (14) are made of electrically conducting paint and/orelectrically conducting ink.
 12. A method of producing an illuminatedshelf of a food refrigeration appliance (1) comprising a casing (2); afood refrigeration chamber (3) housed inside said casing (2); and alighting system (7), in turn comprising a number of light sources (7 a),and power means (8, 10) for electrically powering said light sources (7a) ; said shelf (5) having a first food-supporting surface and a secondopposite surface and being located inside said refrigeration chamber(3); and said method being characterized by comprising the step ofassociating a number of light sources (7 a) and a number of electricallyconductive tracks (14) to at least one of said surfaces of the saidshelf (5) to define an electric circuit (9) connecting light sources (7a) to said power means (8, 10) and applying a protective layer (18) ofelectrically insulating material applied to at least one of saidsurfaces of the shelf (5).
 13. A method of producing an illuminatedshelf of a food refrigeration appliance (1) comprising a casing (2); afood refrigeration chamber (3) housed inside said casing (2); and alighting system (7), in turn comprising a number of light sources (7 a),and power means (8, 10) for electrically powering said light sources (7a) ; said shelf (5) having a first food-supporting surface and a secondopposite surface and being located inside said refrigeration chamber(3); and said method being characterized by comprising the steps of:associating a number of light sources (7 a) and a number of electricallyconductive tracks (14) to at least one of said surfaces of the saidshelf (5) to define an electric circuit (9) connecting light sources (7a) to said power means (8, 10); providing said light sources (7 a) andsaid electrically conductive tracks (14) on a supporting sheet (16) ofelectrically insulating material; and applying said supporting sheet(16) to at least one of said surfaces of the shelf (5).
 14. A method asclaimed in claim 13, comprising the step of depositing electricallyconductive material on said supporting sheet (16) so as to form saidelectrically conductive tracks (14).
 15. A method as claimed in claim13, comprising the step of providing said supporting sheet (16) with atleast an adhesive surface (16 a).
 16. A method as claimed in claims 12,comprising the step of depositing electrically conductive material on atleast one of said surface (5 a) of said shelf (5) to form saidelectrically conductive tracks (14).
 17. A method as claimed in claim16, comprising the step of applying a protective sheet (18) ofinsulating material to at least one of said surface (5 a) of the shelf(5) or to a supporting sheet (16) of electrically insulating material soas to cover the electrically conductive tracks (14).
 18. A method asclaimed in claim 16, comprising the step of applying a number of lightemitting diodes (15) to at least one of said surface (5 a) of the shelf(5) or to said supporting sheet (16).
 19. A method as claimed in claim16, comprising the step of stamping a number of lines of electricallyconducting ink and/or electrically conducting paint on said surface (5a) of said shelf (5).